Visual Studio Code Dev

Visual Studio Code is a free, lightweight and powerful code editor for Windows, Mac and Linux, based on Electron/Chromium. It has built-in support for JavaScript, TypeScript and Node.js and a rich extension ecosystem that adds intellisense, debugging, syntax highlighting etc. for many languages (C++, Python, Go). It works without too much setup. Get started here.

It is NOT a full-fledged IDE like Visual Studio. The two are completely separate products. The only commonality with Visual Studio is that both are from Microsoft.

Here's what works well:

Editing code works well especially when you get used to the keyboard shortcuts. VS Code is very responsive and can handle even big code bases like Chromium.

Git integration is a blast. Built-in side-by-side view, local commit and even extensions for history and blame view.

Debugging works well, even though startup times can be fairly high (~40 seconds with gdb on Linux, much lower on Windows). You can step through code, inspect variables, view call stacks for multiple threads etc.

Opening files and searching solution-wide works well now after having problems in earlier versions.

Building works well. Build tools are easy to integrate. Warnings and errors are displayed on a separate page and you can click to jump to the corresponding line of code.

Updating This Page

Please keep this doc up-to-date. VS Code is still in active development and subject to changes. This doc is checked into the Chromium git repo, so if you make changes, read the documentation guidelines and submit a change list.

All file paths and commands have been tested on Linux. Windows and Mac might require a slightly different setup (e.g. Ctrl -> Cmd). Please update this page accordingly.

Setup

Installation

Follow the steps on https://code.visualstudio.com/docs/setup/setup-overview. To run it on Linux, just navigate to chromium/src folder and type code . in a terminal. The argument to code is the base directory of the workspace. VS Code does not require project or solution files. However, it does store workspace settings in a .vscode folder in your base directory.

Fixes for Known Issues

Git on Windows

If you only have the depot_tools Git installed on your machine, even though it is in your PATH, VS Code will ignore it as it seems to be looking for git.exe. You will have to add the following to your settings in order for the Git integration to work:

{"git.path":"C:\\src\\depot_tools\\git.bat"}

Rendering of underscore on Linux

As mentioned in #35901, VS Code will not show underscore (_) properly on Linux by default. You can work around this issue by forcing another font such as the default monospace or changing the font size in your settings:

{//If you want to use the default "monospace" font://"terminal.integrated.fontFamily":"monospace"//If you would rather just increase the size of the font://"terminal.integrated.fontSize":15//If you would rather decrease the size of the font://"terminal.integrated.fontSize":15}

Useful Extensions

Up to now, you have a basic version of VS Code without much language support. Next, we will install some useful extensions. Jump to the extensions window (Ctrl+Shift+X) and install these extensions, you will most likely use them every day:

Toggle Header/Source - Toggles between .cc and .h with F4. The C/C++ extension supports this as well through Alt+O but sometimes chooses the wrong file when there are multiple files in the workspace that have the same name.

Protobuf support - Syntax highlighting for .proto files.

you-complete-me - YouCompleteMe code completion for VS Code. It works fairly well in Chromium.

If it fails with “Your C++ compiler does NOT fully support C++11.” but you know you have a good compiler, hack cpp/CMakeLists.txt to set CPP11_AVAILABLE true.

On Mac, replace the last command above with the following.

$ ./build.py --clang-completer --system-libclang

The following extensions might be useful for you as well:

Annotator - Git blame view.

Git History (git log) - Git history view.

chromium-codesearch - Code search (CS) integration, see Chromium Code Search, in particular open current line in CS, show references and go to definition. Very useful for existing code. By design, won't work for code not checked in yet. Overrides default C/C++ functionality. Had some issues last time I tried (extensions stopped working), so use with care.

change-case - Quickly change the case of the current selection or current word.

Instant Markdown - Instant markdown (.md) preview in your browser as you type. This document was written with this extension!

Clang-Format - Format your code using clang-format. The C/C++ extension already supports format-on-save (see C_Cpp.clang_format_formatOnSave setting). This extension adds the ability to format a document or the current selection on demand.

F12 jumps to the definition of the symbol at the cursor (also available on right-click context menu).

Shift+F12 or F1, CodeSearchReferences, Return shows all references of the symbol at the cursor.

F1, CodeSearchOpen, Return opens the current file in Code Search.

Ctrl+D selects the word at the cursor. Pressing it multiple times multi-selects the next occurrences, so typing in one types in all of them, and Ctrl+U deselects the last occurrence.

Ctrl+K, Z enters Zen Mode, a fullscreen editing mode with nothing but the current editor visible.

Ctrl+X without anything selected cuts the current line. Ctrl+V pastes the line.

Setup For Chromium

VS Code is configured via JSON files. This paragraph contains JSON configuration files that are useful for Chromium development, in particular. See VS Code documentation for an introduction to VS Code customization.

Workspace Settings

Open the file //tools/vscode/settings.json5, and check out the default settings there. Feel free to commit added or removed settings to enable better team development, or change settings locally to suit personal preference. Remember to replace <full_path_to_your_home>! To use these settings wholesale, enter the following commands into your terminal while at the src directory:

Tasks

Next, we'll tell VS Code how to compile our code and how to read warnings and errors from the build output. Open the file //tools/vscode/tasks.json5. This will provide 5 tasks to do basic things. You might have to adjust the commands to your situation and needs. To use these settings wholesale, enter the following command into your terminal:

$ cp tools/vscode/tasks.json5 .vscode/tasks.json

Launch Commands

Launch commands are the equivalent of F5 in Visual Studio: They launch some program or a debugger. Optionally, they can run some task defined in tasks.json. Launch commands can be run from the debug view (Ctrl+Shift+D). Open the file at //tools/vscode/launch.json5 and adjust the example launch commands to your situation and needs. To use these settings wholesale, enter the following command into your terminal:

$ cp tools/vscode/launch.json5 .vscode/launch.json

Key Bindings

To edit key bindings, press Ctrl+K, Ctrl+S. You‘ll see the defaults on the left and your overrides on the right stored in the file keybindings.json. To change a key binding, copy the corresponding key binding to the right. It’s fairly self-explanatory.

You can bind any command to a key, even commands specified by extensions like CodeSearchOpen. For instance, to bind CodeSearchOpen to F2 to , simply add { "key": "F2", "command": "cs.open" },. Note that the command title CodeSearchOpen won't work. You have to get the actual command name from the package.json file of the extension.

If you are used to other editors, you can also install your favorite keymap. For instance, to install eclipse keymaps, install the vscode-eclipse-keybindings extension. More keymaps can be found in the marketplace.

Some key bindings that are likely to be useful for you are available at //tools/vscode/keybindings.json5. Please take a look and adjust them to your situation and needs. To use these settings wholesale, enter the following command into your terminal:

$ cp tools/vscode/keybindings.json5 .vscode/keybindings.json

Tips

The out folder

Automatically generated code is put into a subfolder of out/, which means that these files are ignored by VS Code (see files.exclude above) and cannot be opened e.g. from quick-open (Ctrl+P). As of version 1.21, VS Code does not support negated glob commands, but you can define a set of exclude pattern to include only out/Debug/gen:

Using VS Code as git editor

Add [core] editor = "code --wait" to your ~/.gitconfig file in order to use VS Code as editor for git commit messages etc. Note that the editor starts up significantly slower than nano or vim. To use VS Code as merge tool, add [merge] tool = code.

Task Names

Note that we named the tasks 1-build_chrome_debug, 2-build_chrome_release etc. This allows you to quickly execute tasks by pressing their number: Press Ctrl+P and enter task <n>, where <n> is the number of the task. You can also create a keyboard shortcut for running a task. File > Preferences > Keyboard Shortcuts and add { "key": "ctrl+r", "command": "workbench.action.tasks.runTask", "when": "!inDebugMode" }. Then it's sufficient to press Ctrl+R and enter <n>.

Working on Laptop

Because autocomplete is provided by the You-Complete-Me extension, consider disabling C/C++ autocomplete and indexing to save battery. In addition, you might want to disable git status autorefresh as well.

Unable to open $File resource is not available when debugging Chromium on Linux

Chromium recently changed the file path to be relative to the output dir. Check gn args out/$dir --list if strip_absolute_paths_from_debug_symbols is true (which is the default), set cwd to the output dir. otherwise, set cwd to ${workspaceRoot}.